My 2.8 is running like crap. The code it throws relates to the Vehicle Speed Sensor. This part is located in the trans tail section, right? What exactly does it do? What would be the symptoms of a malfunctioning VSS? I've used the search function with no satisfactory results. I'd love to get my Camaro back up and running again so any help is appreciated!

 

The VSS is the Variable Speed Sensor. Basically, its for your speedo. It tells the car how fast its turning the computer with translate that into MPH for you. I believe its mounted on the drivers side of the tranny and should be only one to two wires. Your speed indication my be off unnoticelly or by a few miles per hour.

 

My car has a cable driven speedo.

 

If that's the case, the VSS is the yellow box on the back of the instrument cluster. There is a brown (IIRC) wire connecting it to the ECM. Not knowing the pinout of your one-year ECM, I couldn't tell you which terminal it's in. However, if the engine is running like crap when not at speed, you have other problems besides the VSS. The VSS just tells the ECM when the vehicle is moving, so that the ECM can make adjustments to the fuel and spark curves on the highway or cruising (lean cruise mode).

Best thing I would say to do is to pull the spark plugs to tell how the engine is running (rich or lean). When was the last time you did a tune up? Beware that a sensor may be out of range but not enough for the ECM to throw a code (CTS, MAF, O2S).

Oh, and the guy above is posting some misleading info... The VSS (Vehicle Speed Sensor) sends a signal to a signal buffer that will send a modifed signal to the ECM and to the cruise control module on your car (since your speedo is cable driven). It's in the 90+ models that the VSS connects directly to the ECM and not through a buffer, where the ECM sends signals out to both the cruise module and the speedo head.

 

I've heard of that yellow box referred to as the VSS buffer. Is that the same thing? The engine idles perfectly fine. It runs poorly when driving. I did a full tune up in October and this is not my daily driver. BTW, I have a T5, so no cruise control.

 

Yes, the yellow box is the signal buffer. You may want to hop on over to the ECM board and see if you can get a pinout for your ECM, as you will need to check for a signal on that (brown?) wire that runs between the buffer and the ECM. Your car may not have cruise control, but all that means is that the VSS signal wire that would run to the cruise module (red, IIRC) ends in a 6-wire connector that isn't connected to anything because the cruise control harness is not installed (separate harness from dash harness).

Once you get the pinout, then someone can help you with the flow chart for code 24.

 

Not misleading, just simplified, although overly simplified. After re-reading I did realize I didn't add info that I should've

 

Hey RSFreak, I have a world class t5 on my camaro and I have cruise control. I don't know if they didn't offer it on the 2.8 but I have a 92 RS 305 with a t5 trans and I have cruise control. But I'm trying to hook up a switch to my VSS so I can turn the sensor off and be able to not hit the rev limiter at 110mph. the technical article on thirdgen didn't help much so I'm trying to do a little better research.